geo layer dataset should always override primary

bug:
`geodf` contains 20 rows.
`points` is a List of points of size 20.

```
geodf.plot {
geoMap()
geoPoints(points)
}
```

leads to error.

Start by reproducing the issue with the geodf, points, geoMap(), and geoPoints() example from the report. Trace how these layers are combined and identify why equal-sized inputs produce an error. Done means the example runs successfully with the geo layer overriding the primary layer.

Written by the indexing model from the issue text.